   [machine-state opcode]
   (let [reg-x-num (utils/get-nibble1 opcode)
         reg-x-val (machine-state/get-register machine-state reg-x-num)]
-    (log/info (format "0x%04x FX18 0x%04x sst V[%d](0x%02x)" 
-                       (machine-state/get-pc machine-state) opcode reg-x-num reg-x-val))
+    (trace machine-state opcode "FX18 sst V[%d](0x%02x)" reg-x-num reg-x-val)
     (state/set-sound-timer reg-x-val)
     (machine-state/increment-pc machine-state)))
 

  [machine-state opcode]
  (let [reg-x-num (utils/get-nibble1 opcode)
        reg-x-val (machine-state/get-register machine-state reg-x-num)]
    (log/info (format "0x%04x FX29 0x%04x gfa V[%d](0x%02x)" 
                       (machine-state/get-pc machine-state) opcode reg-x-num reg-x-val))
    (-> machine-state
        (machine-state/set-addr-reg (* reg-x-val 5))
        (machine-state/increment-pc))))

        reg-y-num (utils/get-nibble2 opcode)
        reg-y-val (machine-state/get-register machine-state reg-y-num)
        result (bit-and reg-x-val reg-y-val)]
    (trace machine-state opcode "8XY2 bnd V[%d](0x%02x) = V[%d](0x%02x) & V[%d](0x%02x)" reg-x-num result reg-x-num reg-x-val reg-y-num reg-y-val)
    (-> machine-state
        (machine-state/set-register reg-x-num result)
        (machine-state/increment-pc))))
